1. 放下,降低;使失望：let alone 不干涉;不碰 | let down 放下;降低;使...失望 | let go 放开;释放;发射

2. 使失望：leave out 省略 | let down 使失望 | let sb. down 让某人失望

3. 放下：let daylight into 明朗 | let down 放下 | let drive at 对准打

1.

verb

1. fail to meet the hopes or expectations of

e.g. Her boyfriend let her down when he did not propose marriage

Synonym: disappoint

2. move something or somebody to a lower position

e.g. take down the vase from the shelf

Synonym: lowertake downget downbring down