improve,understand,start,decide,travel造句

My English level is so so,I need improving it.
We undertook the task apraidly .
We started to learn Keroan last Sunday.
I decide to buy some flowers to my mother during the Mother's day.
I wish I can travel around the world.

I don't understand what you said.
A true friend will understand all that you said and did.
I have decided to go abroad (国外）.
I haven't decided whether to go or not.
I will go traveling next week.
Recently I have a series of travel plans.(一系列出行计划）
I'm improving my English all the time.
Though I'm working hard,I didn't improve my English very much.
Let's start working.
Just start and do it.