Заполните пропуски в инструкции следующими фразами
1_______, clean it with a petrol-moistened cloth.
If the terminals are dirty, clean them with 2_______.
If the brushes are worn, 3_______.
If the grooves on the commutator are clogged, use a small file 4_______ them.
If the commutator is dirty
a pin
replace them.
to clean