at/on sight

1. 一见（就）
   They had orders to shoot on sight.

   他们接到命令说见人就开枪。

at first sight

1. 初见；初看之下
   They fell in love as soon as they met: it was love at first sight.

   他们一见面就坠入情网，真是一见钟情。

at (the) sight of

1. 一看见
   At the sight of the police officers they ran off.

   一看见那些警官，他们便逃跑了。

catch sight of

1. 看到
   I caught sight of her hurrying away but I didn't try to speak to her.

   我看见她匆忙走开，但我并没有跟她讲话。

in sight

1. 看得见
   No car is in sight.

   一辆汽车也看不见。

lose sight of

1. 不再看见
   I've lost sight of that bird.

   我看不到那只鸟了。

out of sight

1. 在看不见的地方
   The train was soon out of sight.

   那火车很快就看不见了。

2. 好极了；太棒了；十全十美
   That birthday gift was really out of sight.

   那件生日礼物实在是太棒了。

   His new sports car is really out of sight.

   他的新跑车实在太棒了。

set one's sights on

1. 力求
   We have set our sights on a bigger house.

   我们一心想买幢大一点的房子。

• at first sight
  when first seen; from an initial impression.
• in sight
  
  1. visible.
  2. close to being achieved or realized.
• in (or within) sight of
  
  1. so as to see or be seen from.
  2. within reach of; close to attaining.
• in (or within) one's sights
  
  1. visible, especially through the sights of one's gun.
  2. within the scope of one's ambitions or expectations.
• lose sight of
  
  1. be no longer able to see.
  2. fail to consider, be aware of, or remember.
• on (or at) sight
  as soon as someone or something has been seen.
• out of sight
  
  1. not visible.
  2. (also outasight) informal extremely good; excellent.
• raise (or lower) one's sights
  become more (or less) ambitious; increase (or lower) one's expectations.
• set one's sights on
  hope strongly to achieve or reach.
• a sight ——
  informal indicating considerable extent:
  she is a sight cleverer than Sarah.
• a sight for sore eyes
  informal a person or thing that one is extremely pleased or relieved to see.
• a sight to behold
  a person or thing that is particularly impressive.