Yet there is a dark side to this picture: despite our progress, half of the world's population still suffers, with water services inferior to those available to the ancient Greeks and Romans.

然而，这种情况也有其黑暗的一面：尽管我们取得了进步，世界上仍有一半的人口在受苦，供水服务还不如古希腊和古罗马人。

youdao

Just rub the cut side of half a lemon all over them and buff with a soft cloth.

只需用半个柠檬的切面擦拭它们全部，然后用软布擦亮即可。

youdao

Therefore, people who have suffered a serious stroke on the left side of the brain without suffering any such impairment must have their language centers in the right half.

因此，那些左脑严重中风却没有任何损伤的人，他们的语言中枢一定在右半脑。

youdao

Trailing 10-6, the Saints surprised the Colts by starting the second half with an on-side kick.

VOA: standard.2010.02.08

But either side of that - and the opportunities for Paul Robinson and Schofield either side of half-time - the game was generally well controlled by the hosts.

BBC: Sport - Football - Ipswich 2-0 Millwall

Fortunately for the slightly shell-shocked home side, fly-half Jones had kept them ticking over on the scoreboard and his third penalty after just 18 minutes meant the Scarlets only trailed 9-12.

BBC: Scarlets 43-34 Perpignan

After Dave Walder and Ryan Davis traded penalties to leave Wasps with a 9-6 lead, tries either side of half-time put the hosts in charge.

BBC: Wasps 24-12 Exeter Chiefs