下列各项中属于生态系统的是：

我国是世界上季风气候最显著的地区，其主要原因是（     ）

    Low-Cost Gifts for Mother's Day Gift

    Gift No. I

    Offer to be your mother's health friend. Promise to be there for any and all doctor's visits whether a disease or a regular medical check-up. Most mothers always say “no need,” another set of eyes and ears is always a good idea at a doctor's visit. The best part ? This one is free.

    Gift No. 2

    Help your mother organize all of her medical records, which include the test results and medical information. Put them all in one place. Be sure to make a list of all of her medicines and what times she takes them. “Having all this information in one place could end up saving your mother's life,” Dr. Marie Savard said.

    Gift No. 3

    Enough sleep is connected to general health conditions. “Buy your mother cotton sheets and comfortable pillows to encourage better sleep,” Savard said. “We know that good sleep is very important to our health.”

    Gift No. 4

    Some gift companies such as Presents for Purpose allow you to pay it forward this Mother's Day by picking gifts in which 10 percent of the price you pay goes to a charity (慈善机构). Gift givers can choose from a wide variety of useful but inexpensive things ---- many of which are “green” ---- and then choose a meaningful charity from a list. When your mother gets the gift, she will be told that she has helped the chosen charity.