Đáp án là: from ⇒ to.

Sao trùng hợp thế .-.

1. can't => couldn't

2. what => how 

3. happy => unhappy

4. happen => happens

5. staying => to stay 

B -> NERVOUSLY
B -> WHAT HAPPENED
C -> PARTICIPATE IN
A -> ALTHOUGH
D -> ISOLATED FARM

6. In spite of -> Instead of

7. am meeting => meet

8. which -> where 

9. cuts -> cut

10. am needing -> need

1 B => was made

2 C => has just been thrown

3 A => Most

4 D => perfect accuracy

5 D => weighs

6 B => which is

7 B => had finished

8 A => had never sold

9 A => when

10 C => which

mờ quá bạn ah

1 D => had left

2 D => I'm not used to

3 B => work

4 B => learn

5 B=> have to do

6 B => which

7 C => to work

8 C => meeting

9 C => to come

10 C => bỏ

1 D ⇒ had left

2 D ⇒ I'm not used to

3 B ⇒ work

4 B ⇒ learn

5 B ⇒ have to do