He is used to ( doing) hard work.
他习惯于（干）艰苦工作。
This idiom is used to describe doing evil things in collusion with others.
这个成语比喻坏人相互勾结起来做坏事。
Put together, this idiom is used to describe someone doing things very seriously without any careless.
合起来看，“一丝不苟”这一成语用来形容办事认真、仔细，一点也不马虎。
That is because women can continue to do something they are used to doing.
那是因为妇女能继续做他所一直习惯做的事情。
When we are used to doing things, we naturally react quickly.
我们做事习惯以后，自然就会反应快。