But let no one think that pleasure is immoral. Pleasure in itself is a great good, all pleasure, but its consequences may be such (31) the sensible person eschews certain varieties of (32) Nor need pleasure be gross and sensual. They are wise in their generation (33) have discovered that intellectual pleasure is the most satisfying and the most enduring. It is well to (34) the habit of reading. There are (35) sports in which you can engage to your own satisfaction after you have passed the prime of life; there are no games except patience, chess problems and crossword puzzles that you can play without someone to play them with you. Reading suffers (36) no such disadvantages; there is no occupation—except perhaps needle- work, but that leaves the restless spirit (37) liberty—which you can more easily (38) up at any moment, for any period, and more easily put (39) when other calls press upon you; there is no other amusement that can be obtained in these happy days of public liberties and cheap editions at so small a (40) . To acquire the habit of reading is to construct for yourself a refuge from almost all the miseries of life.

A．his

B．its

C．it

D．him

斜管沉淀池和其他沉淀池相比，优点有（）。

A、占地小、效率高

B、造价低

C、管理方便

D、不需维护设备