1)an , a ,
2)а ,an
3)an, a
4)an, a !
т.е . если следующее слово начинается на гласную , то предлог должен кончатся на согласную . А если слово после предлога начинается на согласную ,то тогда пишем просто :a
I visit my friends -<em> Present Simple</em>
I visiting my friends - <em>Present Continuous</em>
I have been visiting my friends - <em>Present Perfect Continuous</em>
I have visited my friends - <em>Present Perfect</em>
I visited my friends - <em>Past Simple</em>
I was visiting my friends - <em>Past</em><em> Continuous</em>
I had been visiting my friends<em> - <em>Past</em><em><em>Perfect</em> Continuous</em>
</em>
I had visited my friends - <em>Past</em><em>Perfect</em>
<em>
</em>
I will visit my friends<em> - <em>Future </em>Simple
</em>
<span>I will be visiting my friends - <em><span>Future Continuous</span></em></span>
<span><span><span>I will have been visiting my friends</span></span><em><span><span>- <em><em><em>Future Perfect</em> Continuous</em></em>
</span></span></em></span>
<span><span>I will have visited </span><span>my friends</span><span> - </span><em><span><span>Future Perfect</span></span></em></span>
<span><em /><span>
</span></span>
С 20-22(призывной возраст)
Gets
is
goes
is
does
has
goes
takes
speaks
begins
get
switch
do
takes
have
leave
takes
is
leaves
gather
watch
talk
Утвердительная
I like helping my parents at home. It's not difficult for me to wash the floors or wipe the dust off the shelves. I like helping my mother cook food or finding fault with the arrival of guests. I think that home affairs are important, because that's how we become responsible. when my mother asks me to wipe the mirrors, I do it because I want to please my parents, I do not want to fail my mother. I want my parents to know that they can rely on me .