Past, Present, Future and Conditional are common tenses in any language. Begin learning these forms. Use Vocabulix to memorize the various tenses online and free.
Richard, UK: 'It is good that one can save the lessons and continue at a later stage. Will you add the same for the verb lessons any time soon?'
'The major problems we face can't be resolved at the same level of thinking we were at when we created them.' - Einstein