帮忙看下这些句子的语法问题吧After scoring ten goals in the first half of the competition,the soccer players thought that they had ensured victory.想问一下这里用had ensured的意思是什么?还有如果had ensured victory 那部分改成a victory they would ensure为什么不对呢?After he won the relay relatively easily,he decided to continue his training program and even to enter more races.这里的won为什么错了呢?难道要改成had 但是after不是已经表明了时间先后顺序么?Her parents' marriage gift cannot be compared with any present that was given

ensure sth确保某事，ensure victory确保胜利
按照你的说法“如果had ensured victory 那部分改成a victory they would ensure”，则替换为：
After scoring ten goals in the first half of the competition, the soccer players thought that they had ensured victory.
→After scoring ten goals in the first half of the competition, the soccer players thought that they a victory they would ensure.自己看看行不行啊，句子都不通的
况且，原句的后半部分是是一个宾语从句：the soccer players thought that they had ensured victory球员认为他们已经确保胜利了。
after是个连词，意为“...之后”，但它不影响你原本的思维——“赢得接力赛”发生在“决定继续参加别的比赛”之前，故可以用过去完成时（不过话说回来，我觉得你用一般过去时是可以接受的）
我倒觉得any present没问题，倒是那个时间的表达“at the time”和“was”和cannot三者时态不一致。

1. ensured 改为 asured 2. 其实用一般过去时也不能说错.但要是死扣语法,就得用had won, 毕竟过去完成时强调过去时间或行为的完成.3. 应该说any other present.marriage gift 是她收到的礼物之一,应该与她所收到的...