Practice, practice, practice...

/i:/ vs. /ɪ/

English has two close vowels: /i:/ and /ɪ/, where Portuguese only uses a sound closer to /i/, so Portuguese-speakers need to relax the mouth more to make /ɪ/:

feet / fit, leave / live, green / grin, seep / sip, deed / did

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 /h/

Portuguese-speakers sometimes miss the /h/ sound – though there are some exceptions (honour, vehicle) it is normally pronounced:

Hi Harry, how was your holiday in Hastings?