I've studied how to use 'just', 'already' and 'yet' in grammar lessons. 'Just' is used when it has been a short time. 'Already' is used if I did it before. 'Yet' is used in questions and negative sentences. Each word is used in both the 'P…

I've been studying the present perfect. Present perfect is an action from past to present. It almost seems too simple. Present perfect uses 'for' and 'since', but doesn't use 'ago'. 'For' is duration. ex) I've been in Tokyo for two years. …