Present perfect tense vs simple past tense | http://www.engames.eu/present-perfect-vs-past-simple_t/
English grammar - verb tenses timelines
All modal verbs are auxiliary verbs, which means they can only be used with a main verb. Modal verbs cannot be a main verb. They are used to express ideas such as possibility, prediction, speculation, deduction and necessity.
I share with you the complete list of phrasal verbs I used during 10 days in a row. Now it's your turn to use the same strategy and learn phrasal verbs too