grip, hold on to

I hold on to the strap.

私はつり革を握ります

I hold on to the strap with both hands.

私は両手でつり革を握ります

I always hold on to the strap with both hands.

私はいつも両手でつり革を握ります

I always hold on to the strap with both hands on the subway.

私は地下鉄でいつも両手でつり革を握ります

I always hold on to the strap with both hands on the subway when it stops suddenly.

私は、急停車するとき地下鉄でいつも両手でつり革を握ります