Miss the boat — 错失良机.
On cloud nine — 欣喜若狂.
Once in a blue moon — 千载难逢.
Piece of cake — 小菜一碟.
Out of the blue — 突如其来.
An elephant’s memory — 过目不忘.
Spick and span — 一尘不染.
Heart of gold — 菩萨心肠 / 赤子之心.
Under the weather — 身体不适 / 微恙在身.
Hit the sack — 倒头就睡 / 酣然入梦.

Down and out — 穷困潦倒 / 一蹶不振.
Drop-dead gorgeous — 倾国倾城 / 貌美如花
Early bird — 捷足先登 / 早起的鸟儿
Full of beans — 精力充沛 / 生龙活虎
Hustle and bustle — 熙熙攘攘 / 车水马龙
In seventh heaven — 欢天喜地 / 乐不可支
Inside and out — 了如指掌 / 彻头彻尾
With flying colours — 大获全胜 / 金榜题名
Without a hitch — 一帆风顺 / 万无一失
Over the moon — 喜出望外 / 心花怒放

Miss the boat - Miss an opportunity
On cloud nine - Extremely happy
Once in a blue moon - Rarely
Piece of cake - Very easy
Out of the blue - Unexpectedly
An elephant’s memory - A very good memory
Spick and span - Neat and clean
Heart of gold - Very kind and generous
Under the weather - Feeling sick or unwell
Hit the sack - Go to sleep

Down and out - Having no money or job
Drop-dead gorgeous - Extremely attractive
Early bird - A person who wakes up early
Full of beans - Full of energy
Hustle and bustle - Busy and noisy activity
In seventh heaven - Extremely happy
Inside and out - In great detail; thoroughly
With flying colours - With great success
Without a hitch - Without any difficulty
Over the moon - Extremely happy