1.i think you should recycle these plastic  carrier bags
--> If i ..........................................
2.people speak english and french in Canada
-->english and french ...............................
3. this morning , i ate bread then i went to school 
-->before i went .................................
4 . lan was ill , so she didn't go to school this morning
-->because ......................
5.A storm destroved roads in our village
-->Roads.................................................
6.people are not aware of keeping environment clean , they throw garbage in the streets
--->If.............................................................
7.there was a loud noise next to my door last night ,so i couldn't sleep
----->because......................................................
8.the storm destroyed many houses in this village last week
---->many houses................................................
9. we use water carefully ,we have fresh water
-->If...........................................
10.David had gone home before we arrived 
-->after......................
11. although he was ill. he went to school yesterday
-->despite.......................
12.i am not you , but i think you should recycle these plastic carrier bags
-->If ..............................
13.this morning , i ate bread then i went to school
-->before i went.......................
14.people destroyed forest , so there is a lot of flood now
-->If.................................

Hai người đi xe máy, người thứ nhất đi quãng đường 15km hết 30phút, người thứ hai đi quãng đường 8000m trong thời gian 10phút.

a.     Người nào đi nhanh hơn? Vì sao?

b.     Nếu hai người cùng khởi hành một lúc và đi cùng chiều thì sau 15 phút, hai người cách nhau bao nhiêu km?