=>
155. Because he was absent from class, he had an accident.
156. The question isn't easy enough for us to work to find the answer.
We were so late that we couldn't catch the last bus.
157. Although they had made carefully preparations, something went wrong.
158. If you go out without a rain coat, you will get wet.
159. Unless you give these plants water, they will die.
160. If you don't hurry up, you'll be late.
161. Nga asked me why I hadn't applied for the scholarship.
162. If only I hadn't lost control, my car wouldn't have hit the roadside tree.

155, Because he was absent from class, he had an accident.

156, - The question isn't easy enough for us to work to find the answer.
        - We were so late that we couldn't catch the last bus.

157, Although they had made carefully preparations, something went wrong.

158, If you go out without a rain coat, you will get wet.

159, Unless you give these plants water, they will die.

160, If you don't hurry up, you'll be late.

161, Nga asked me why I hadn't applied for the scholarship.

162, If only I hadn't lost control, my car wouldn't have hit the roadside tree.

#LemonXTree