I'll have done it ... the time you arrive. a) –, b) at, c) in, d) by ​

I'll have done it at the time you arrive.

I'll have done it by the time you arrive.

yet before last summer i didn't have an idea where i can spend coolly my spring vacation.

but the last summer holiday that i just spent was extremely interesting and fascinating. it's held on the first of september. i and my eight friends, all pupils of high school # 35, traveled to almaty. we visited many well-known places such as: tamgaly tas, issyk kurgan, medeo, alatau mountain, turgen waterfall. these places gave me so many memories.

at first, we were off at 6 a.m. and visited tamgaly tas. this place is a historic place of first people, ancestors of kazakh nation. we heard many emotional stories about them and about the this place such as: the history of ancient kazakh people, how they developed workmanship and art. i was very surprised when i saw stony pictures of people of bronze and iron periods. there were so many beutiful and unusual pictures describing and depicting animals. after that we visited other places that i mentioned before. and i liked them too. and finally i was impressed by the magic sound of sand on issyk kurgan.

i liked my summer holiday so much. that's why i decided to come to almaty again for this spring vacation.

my younger brother had his birthday on sunday. i proposed to arrange  a birhday party/picnic for him and his friends. "not a bad idea! said my parents.we decided to spend  a weekend in the country. i was responsible  for the social programme.we played funny games and sports, sang songs,danced and took pictures.my brother and his friends enjoyed      the  picnic."that was great",he said and kissed me.

                  next year we are going to arrange a birthday picnic for my brother and his friends again.

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