Complex sentences activity - Free Printable

Let’s go step by step to fill in each blank with the correct subordinating conjunction from the word box:

Word box:
even though, before, since, until, because, when, whenever, while

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1. Samantha is happy _______________ she won the championship.
→ She’s happy *because* of winning.
✔ because

2. Jean cleaned the table _______________ her mom did the dishes.
→ Two things happening at the same time → “while” fits.
✔ while

3. _______________ Dan was sick, he went to work.
→ He went to work *despite* being sick → contrast → “even though”
✔ Even though

4. Samantha can’t relax _______________ her exams are over.
→ She’ll wait *up to the point that* exams end → “until”
✔ until

5. Liza hasn’t seen her aunt _______________ she was a teenager.
→ From that past time up to now → “since”
✔ since

6. Patricia visits the zoo _______________ she loves animals.
→ Reason for visiting → “because” — but we already used “because” in #1? Wait — let’s check if duplicates are allowed. The instructions don’t say no repeats. But looking at the list, there are 8 words and 10 sentences — so some may repeat? Actually, let’s recheck: maybe #6 should be “because”, and #1 also “because”? That’s okay unless told otherwise. But wait — let’s see if another fits better. No — “because” is best here too. But hold on — maybe we can use “whenever”? No, that doesn’t fit as well. Let’s stick with “because” for both? Actually, let’s look again.

Wait — perhaps #1 could be “since”? “Samantha is happy since she won...” — that works too! “Since” can mean “because”. So maybe assign “since” to #1 and “because” to #6? That avoids repetition and uses more variety.

Actually, let’s do this carefully:

#1: “Samantha is happy ___ she won…” → either “because” or “since” work.
#6: “Patricia visits the zoo ___ she loves animals.” → definitely “because” (reason).
So better to use “since” for #1? But “since” is also used for time (#5). Hmm.

Actually, standard usage:
- “Since” = from a past time until now → #5 needs “since”
- “Because” = reason → #1 and #6 both need reason

But we have two reasons — so maybe one gets “because”, one gets “since”? In informal English, “since” can mean “because”, so it’s acceptable.

To avoid repeating, let’s assign:

#1: since (meaning “because”)
#6: because

That way we use different words.

But let’s confirm all others first.

7. We put away our toys _______________ Mom returns from work.
→ We do it *before* she comes back → “before”
✔ before

8. _______________ Brian watered all the plants, I didn’t have to.
→ Because Brian did it, I didn’t need to → “Since” or “Because” — but we’re saving “since” for #1? Wait, we said #1 = since, #6 = because. Then #8? Maybe “Since” again? Or “Because”? Let’s see.

Actually, #8: “___ Brian watered..., I didn’t have to.” → This is cause-effect → “Since” or “Because”. If we used “since” for #1, then #8 can be “Because”? But we want to use all words? Not necessary — just pick the best fit.

Alternatively, maybe #8 is “Since” — and #1 is “Because”? Let’s swap:

Better plan:

Use “because” for #1 (most direct)
Use “since” for #5 (time) and #8 (cause) — but “since” can be used twice? Again, not prohibited.

Actually, let’s list all answers logically without worrying about repetition unless forced.

Re-evaluate:

1. Samantha is happy because she won → clear reason → ✔ because
2. Jean cleaned... while mom did dishes → simultaneous action → ✔ while
3. Even though Dan was sick... → contrast → ✔ even though
4. Can’t relax until exams over → time limit → ✔ until
5. Hasn’t seen aunt since she was teen → from past to now → ✔ since
6. Visits zoo because she loves animals → reason → ✔ because (again? okay)
7. Put away toys before Mom returns → prior action → ✔ before
8. Since Brian watered plants, I didn’t have to → cause → ✔ since (again? okay)
9. Surprised when magician pulled rabbit → at the moment → ✔ when
10. Whenever Mom goes shopping, she brings treat → every time → ✔ whenever

Now check which words we used:

Used:
because (x2), while, even though, until, since (x2), before, when, whenever

Missing: none really — all 8 words are covered, some repeated.

But let’s see if we can avoid repeating “because” and “since”.

Alternative for #6: Is there another word? “Whenever”? No — she doesn’t visit only when she loves animals — that doesn’t make sense. “When”? Possible, but weaker. Best is “because”.

Similarly, #8: “Because Brian watered...” — same as #6.

Actually, the worksheet likely allows reuse — many such worksheets do.

But let’s try to use each word once if possible.

Total blanks: 10
Words given: 8 → so 2 must repeat.

Which ones are safest to repeat? “because” and “since” are versatile.

But let’s assign uniquely where possible.

Try:

1. because
2. while
3. even though
4. until
5. since
6. because ← repeat
7. before
8. since ← repeat
9. when
10. whenever

That’s fine.

But wait — #8: “___ Brian watered all the plants, I didn’t have to.”
Could it be “After”? Not in word box.
“While”? No.
“Before”? No.
Only “since” or “because” fit.

Similarly, #6 only “because” fits well.

So we’ll go with that.

Final assignment:

1. because
2. while
3. Even though
4. until
5. since
6. because
7. before
8. Since
9. when
10. Whenever

Note: Capitalization — for sentence-starting blanks (#3, #8, #10), capitalize first letter.

Check #9: “We were surprised ___ the magician pulled...” → “when” is perfect — at the time it happened.

#10: “___ Mom goes shopping, she brings...” → “Whenever” = every time → perfect.

All good.

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Final Answer:
1. because
2. while
3. Even though
4. until
5. since
6. because
7. before
8. Since
9. when
10. Whenever