You can do this in a virtual choir. Virtual choir members     1     themselves while they     2     alone on video. These videos are     3     onto the Internet, and then they are put together into one video that you can see     4     —a virtual choir.

For example, there are public advertisements, which    1    (鼓励) citizens to participate in improving their neighborhood, protecting the environment, and helping other people. Over the last     2    (十年) , the government has sponsored advertisements to    3    (教育)the public on fighting AIDS, saving water, helping the poor, giving up smoking, etc. These advertisements have helped to increase public    4    (知识)about topics that used to be i    5    (忽略)by most people, and this has made our society a better place for everyone.

An advertisement uses words and pictures to     1     people to buy a product or service, or to believe in an idea. Newspapers, magazines, the Internet, radio and television are the most common places to find them. There are two main types of advertisements—commercial advertisements and public service advertisements (PSAs). A commercial advertisement is     2     which someone has paid for to advertise a product or service. PSAs are often run for free, and are meant to educate people about health, safety, or any other problem that affects public     3    .

We have decided to go for an outing this weekend. Nanao will be our destination.     1     (这是我们第一次外出) to relax ourselves this term. At present, some students     2    （对…感到厌倦）study and some even     3    （失去信心）. In order to keep a balance between work and leisure, we think it’s a good idea for us to go out to breathe the fresh air. Only by getting close to nature     4    （我们才能欣赏美景）and release our pressure, making our study more efficient. What’s more, through the outing, we will find ourselves     5    (为…所着迷) by the power of nature and our friendship     6     (得到增进)greatly. Those     7    （要参加外出活动的）are expected to meet at the school gate at 8:00 this Sunday morning.