Past actions that matter now

**The present perfect = has/have + past participle:** have become, has transformed, have adopted.

It links the past to now. 'Many tribes have adopted this craft' means they took it up in the past and still practise it. It also shows a just-finished action: 'I have just finished the fan.'

**Has or have?**

• has with he, she, it and singular nouns: 'Puppetry has evolved.'
• have with I, you, we, they and plural nouns: 'Puppeteers have mastered it.'

Not with a finished time. Say 'I made it yesterday', not 'I have made it yesterday'. Words like yesterday, last year, in 2010 need the simple past.