can could may shall should modal verbs might will would ought to must This can’t be healthy! I must see a doctor. May I eat this apple? You should exercise more. São verbos auxiliares, portanto a negação é feita com verb + not, e a forma interrogativa é feita com o verbo antes do sujeito: You shouldn’t overeat. May I speak to you in private? Com exceção de ought to, nunca são precedidos ou seguidos de to: We must to visit Rod. Wrong Dedução – Must expressa certeza que sim. He must have the flu. He has all the typical symptons. Possibilidade “...I may be suffering from an eating disorder...” A cure for cancer might never be discovered. You could be developing bulimia. Impossibilidade – can’t expressa certeza que não. Brad can’t be sick. I spoke to him ten minutes ago. Conselho – should e ought to são as formas mais comuns. You should get professional help. You ought to take some vitamin C to prevent influenza. Permissão – can, could ou may podem ser usados. Mais formais Mais informal You can open the window if you like. May I take some of your painkiller? Could we have your book for a few days? You may now kiss the bride. Pedidos / Solicitações – can, could, will e would podem ser usados. Could you buy me some medicine? Can you change this light bulb for me? Will you please reserve a table in the non-smoking area for us? Desejos mais formais - may May the Lord protect you. May you always have good health. Habilidades / capacidades – can e could He can lift very heavy weights at the gym. He could run for miles when he was younger.