Should I (A) interested (B) in that subject, I would try (C) to learn (D) more about it.
A.interested (B)
B.to learn (D)
C.would try (C)
D.Should I (A)

You must read (A) the instructions; otherwise, (B) you hadn’t known (C) how to use (D) it.
A.hadn’t known (C)
B.must read (A)
C.otherwise, (B)
D.how to use (D)

If he hadn’t helped me, I wouldn’t have been so successful.
A.Without his help, I wouldn’t be so successful.
B.Unless he had helped me, I wouldn’t have been so successful.
C.Without his help, I wouldn’t have been so successful.
D.But for he hadn’t helped me, I wouldn’t have been so successful.

Without your assistance, I couldn’t have finished the game.
A.Unless your assistance, I couldn’t finish the game.
B.Had it been for your assistance, I couldn’t have finished the game.
C.But for your assistance, I couldn’t finish the game.
D.If it hadn’t been for your assistance, I couldn’t have finished the game.

Choose the underlined part among A, B, C, or D that needs correction.Won't (A) you be a lot (B) happier if (C) Dad came home (D) this weekend?
A.a lot (B)
B.came home (D)
C.if (C)
D.Won't (A)

If he had (A) a (B) thorough knowledge of English, he could have applied (C) for (D) this post.
A.had (A)
B.a (B)
C.could have applied (C)
D.for (D)

If (A) her condition should (B) improve (C), we inform (D) you immediately.
A.should (B)
B.If (A)
C.improve (C)
D.inform (D)

I didn’t have enough money with me then; otherwise, I would buy that coat.
A.If I had had enough money with me then, I would have bought that coat.
B.If I didn’t enough money with me then, I would buy that coat.
C.If I didn’t enough money with me then, I wouldn’t buy that coat.
D.If I had enough money with me then, I wouldn’t buy that coat.

Plants and flowers can't live without water.
A.Unless you water plants and flowers, they live.
B.If you don't water plants and flowers, they can't live.
C.If you water plants and flowers, they can't live.
D.If you water plants and flowers, they will live.

Without this treatment, the patient would have died.
A.If there hadn’t been this treatment, the patient would have died.
B.Unless this treatment had been, the patient would die.
C.Unless this treatment, the patient will die.
D.If there weren’t this treatment, the patient would die.