In general, the electric-bike is not so dangerous as ______, if ______ following the instructions[ ]

下列诗句中划线词解释不完全正确的一项是（ ）

－＿＿ five yuan enough for a tin of dog food －Of course not.

understanding, a high school graduate hasalready reached a point in his/her life ______ he/she is supposed to makedecisions of his/her own

Where is Tom We can’t find him anywhere. —Perhaps he_____ home.