English perfectly shows the "network effects" of a global tongue: the more people use it, the more useful it is. Parents expect their children {#blank#}1{#/blank#}(master)English, which is encouraging the {#blank#}2{#/blank#}(grow)of private schooling. Education authorities are switching to English medium, in part to control the outflow(外流) of children into the private sector.

Teaching children in English is fine if that is {#blank#}3{#/blank#} they speak at home and their parents are fluent {#blank#}4{#/blank#} it. But that is not {#blank#}5{#/blank#} case in most public and low-cost private schools. Children are taught in a language they don't understand by teachers {#blank#}6{#/blank#} English is poor. The children learn neither English nor anything else.

    Research shows that children learn {#blank#}7{#/blank#}(much)when they are taught in their mother tongue than they do when they are taught in any other language. In a study of children in 12 schools in Cameroon last month, those taught in Kom {#blank#}8{#/blank#}(do)better than those taught in English in all subjects.

    English should be an important subject at school, but not {#blank#}9{#/blank#}(necessary)the language of instruction. Rather than switching to English-medium teaching, governments fearful of {#blank#}10{#/blank#}(lose) custom (光顾) to the private sector should look at the many possible ways of improving public schools.

    The heat wave that broke high temperature records in five European countries a week ago is now over Greenland, {#blank#}1{#/blank#} (cause) the surface of the islands vast ice sheet to melt at near-record levels and a huge {#blank#}2{#/blank#} (lose) of ice in the Arctic. On Wednesday alone, more than 10 billion tons of ice was lost to the oceans by surface melt, which is equal {#blank#}3{#/blank#} about 4,000,000 Olympic-sized swimming pools, said Ruth Mottram, a climate scientist with the Danish Meteorological Institute.

    Melting {#blank#}4{#/blank#} (increase) in recent decades because of climate change and has been decreasing accumulation from snow. Previously, during the 1970s and the 1980s, Greenland lost {#blank#}5{#/blank#} average of 50 billion tons of ice each year. From 2010 to 2018, that figure shot up to 290 billion tons {#blank#}6{#/blank#} (annual). This summer, the extent of the melt could surpass (超过) the record set in 2012, {#blank#}7{#/blank#} about 97% of the ice sheets surface began to melt. NASA-JPL Caltech reported at the time.

Greenland, the worlds largest island, {#blank#}8{#/blank#} (lie) between the Atlantic and Arctic oceans, with 82 per cent of its surface {#blank#}9{#/blank#} (cover) in ice. A June 2019 study by scientists in the U. S. and Denmark said melting ice in Greenland alone will add between 5 and 33 centimeters to the rising {#blank#}10{#/blank#} (globe) sea levels by the year 2100. If all the ice in Greenland melted, which would take centuries, the world's oceans would rise by 7.2 meters.

Many people think that fat-free cookies are a healthier option than a regular cookie, and that{#blank#}1{#/blank#}(choose) a salad is a much better choice than a cheeseburger. But in fact, there are a lot of foods considered as "healthy"{#blank#}2{#/blank#}are packed with hidden calories and sugar. Maybe you are trying your best to pursue healthier snacks,{#blank#}3{#/blank#}many choices are still harmful to your health.

Ideally, snack choices should be based{#blank#}4{#/blank#}the same principles as meal choices. After all, snacks make up an important part of people's daily food intake.

In addition, every person is unique. There isn't a{#blank#}5{#/blank#}(recommend) amount for snacking. It depends on a person's activity level, body size, medical situation, schedule and personal preferences. Some people{#blank#}6{#/blank#}(rare) snack at all, while others gain a{#blank#}7{#/blank#}(significance) part of their daily food intake from snacks throughout the day.

Keeping track of snacking habits can be beneficial, especially if you include notes that mention how each snack{#blank#}8{#/blank#}(contribute) to your personal goals. For example, if eating{#blank#}9{#/blank#}afternoon snack helps you avoid overeating at dinner time, then it may be a wise choice{#blank#}10{#/blank#}(make).