Unit1：

　　1.What factors may weaken one's memory?

　　It is often reported that long-term poor nutrition may affect the functioning of the brain, thus damaging both the long-term and short-term memory. Also harmful to one's memory is lack of water. Elderly people need plenty of water to guarantee their memory works. A third factor is lack of sleep. Without enough sleep, one may feel tired and have difficulty concentrating, not to mention learning things by heart.

　　2. Can you describe some possible advantages of having a poor memory?

　　A poor memory may have some advantages. With the passage of time, the sad memories will fade. Those with a short memory tend to recover faster than those with a tenacious memory. For the same reason, forgetful people may be more ready to forget their daily worries and forgive others for their offenses. With a less retentive mind, they may enjoy life more.

　　3. What can you do to make sure all your relatives and friends are on the guest list for your birthday party?

　　First of all, I would check my address book and tick the names of those I intend to invite. Then, to avoid possible omissions, I would ask some of my close relatives, friends and colleagues to look at my initial list of names. They might suggest one or two additions. In this way, I can reduce the chances of missing those I should invite.