1. I suggest having a day to celebrate for parents.

S + suggest + Ving: đề nghị 

2. Lan stayed up late watching TV, so she is tired.

Clause+ so + clause: vì vậy 

3. The student who sits next to me is from China.

N (người) + who + V 

4. Tornadoes are funnel-shaped storms which pass overland below a thunderstorm. 

N (vật) + which + V / S + V 

5. Do you know the girl who had just gone out?

N (người) + who + V 

6. If you don't bring along a raincoat, you will get wet.

If 1: If + HTĐ, S + will/can/shall .. + V1 

7. If we don't save water, we will have no fresh water to use next time.

If 1: If + HTĐ, S + will/can/shall .. + V1 

8. Although people know water and electricity are shortage, they still water them much.

Although + clause, clause: mặc dù 

1. If I were you, I wouldn't turn on the fan and air-conditioner at the same time.

If 2: If + QKĐ, S + would / could + V1 

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