子供たちは６歳で学校に行き始める。

tbd

Children begin school at the age of six.

Children begin school when they are six years old.

課長が我々に対して、あれこれとうるさく言うのを止めた途端に、何もかもがスムーズに行き始めた。

tbd

As soon as our manager got off our backs, everything started to go off without a hitch.