simple present tense is to be used against habitual actions and where there is no need for furnishing a time or an event. See the examples. Babies learn their language from their manual atmosphere, Jai wrote exam well. These sentence want the matter alone and not the time. Whenver a matter needs time it also needs any tense other than simple. Better use simple tense when you comment any thing while witnessing. understand, cricket commentry is given in simple tense while and commentor witnessing the game.