Question

1. Someone has eaten / ate all the cakes  

2. Children have visited / visited their Granny three days ago                                                                                   

 

 

 

Answer 1

1. Someone has eaten all the cakes  

2. Children visited their Granny three days ago                                                                                   

Answer 2

has eaten

visited

 

В первом важен результат, а во втором есть явное указание на время.