learn japanese quickly

I brought back my kids of 4 and 7 yrs. old here in Japan, from Philippines. They`ve been there for 3 yrs. and they can not comprehend japanese anymore. They will be going to school nxt week, and I`m worried for them. Any ideas or suggestions pls. thanks.

For the 4 year old, it's not going to be a huge deal. He/she will adapt fast.

The seven year old may be frustrated for awhile, but will also catch on fast.

There isn't really a fast way to teach them.

Children adapt faster than grown-ups think. There is no quick way to learn the language, but your children will absorb bits of the language every day, from their friends at school, from their lessons, and TV and everything. Don't wory, it may take a while, so just be there for them when initially they could feel a bit left out :)

I would not worry about their Japanese. They may forget their first language though.