1. speed up 加速
I had already taken steps to speed up a solution to the problem.
我已经采取措施加快解决这个问题
。2. make up 组成;弥补
Nothing can make up for the loss of a child.
失去一个孩子是任何东西都无法弥补的
。3. catch up 追赶;赶上
He stopped and let her catch up with him.
他停下了,让她赶上自己
。4. in order to 为了
He only gave his consent in order to gratify her wishes.
他只是为满足她的愿望才同意的
。