在 'high-tech' 中应该有一个连字符。

There should be a ___hyphen in "high-tech."

别忘了在 'mother-in-law' 中使用连字符。

Don't forget to use a ___hyphen in 'mother-in-law'.

单词 'self-esteem' 是带连字符书写的。

The word 'self-esteem' is written with a ___hyphen.