under

below, beneath, under, underneath

这些前置词均可表示位置“在……下面”之意。
below: 指位置低于某物或在某物下方，但不一定在正下方，所指范围较宽。
beneath: 书面用词，指紧挨……之下，其反义词是on。
under: 普通用词，与over相对，指在某物的正下方，含垂直在下的意思。
underneath: 书面口语均用，也常与beneath和under换用，但更含遮蔽的意味。

形容词 under:

1. located below or beneath something else
   同义词：nether
2. lower in rank, power, or authority

副词 under:

1. down to defeat, death, or ruin
2. through a range downward
3. into unconsciousness
4. in or into a state of subordination or subjugation
5. below some quantity or limit
6. below the horizon
7. down below
8. further down
   同义词：below

1. He's very much under the influence of the older boys.
   那些比他大的男孩对他影响很大。
2. She pushed all her hair under a headscarf.
   她把头发都让头巾罩住。
3. If it's not under sport, try looking under biography.
   要是在运动类中查不到，可以查查传记类。
4. She felt herself going under.
   她感到渐渐失去了知觉。
5. If you take a deep breath you can stay under for more than a minute.
   只要深吸一口气就能在水里待上一分多钟。
6. She sat very still under the tree.
   她在树底下静静地坐着。