Make full sentences using the words given

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5. The volunteers will not leave ________ they finish collecting the trash there.
A. after
B. if
C. until
D. no sooner than

V. Make full sentences, using the words given:
1. Not / forget / turn off / lights / when / you / go / sleep.
→ .............................................................................
2. After / Earth Hour / over, / we / save / a lot of / power.
→ .............................................................................
3. All / us / should / follow / 3Rs / conserve / natural resources.
→ .............................................................................
4. If / we / want / save / environment, / we / need / stop / use / so much energy.
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