[译] 他们养成了每天做早操的习惯，因此他们比以前强壮的多。
[误] They make a rule to do morning exercises every day, so they are much stronger.

[正] They make it a rule to do morning exercises every day, so they are much stronger.
[注] “make something a rule” 是“形成规律”、“养成习惯”的意思，在这种结构中，常用it作形式宾语，用不定式或从句作真正的宾语放在后面。