"Lo que des a los niños, los niños darán a la sociedad"

Do we have to use for or since while we are talking about present perfect? The diference between for and since is easy:  FOR is used when we are talking about  a period of time: four days, two weeks, one hour, ... SINCE is used when the are describing a centain point in time: since I was five years old, since last week, since 2007... KAHOOT FOR OR SINCE KAHOOT FOR OR SINCE II

We use the present perefect to talk about an activity that started in the past and continue now  or has finished recently. The structure of this tense is the following: AFF: Subj + HAVE/HAS + past participle + complements I have eaten pasta. She has gone to London. NEG : Subj + HAVE/HAS + not + past participle + complements. I have not eaten pasta/ I haven't eaten pasta. She has not gone to London. / She hasn't gone to London. INT: HAVE/HAS + subj + past participle+ complements ?   Have I eaten pasta?  Has she gone to London?  Now is time for you to practice: PRESENT PERFECT PRESENT PERFECT KAHOOT   PRESENT PERFECT KAHOOT II