1.ideographic a．表意文字（符號(hào)）的(of or relating to ideogram)

詞根記憶：ideo(=idea思想，意義)+graph(寫)+ic--把意義記錄下來(lái)的一表意文字的

例：Chinese consists of tens of thousands of ideographic characters.

2.ideology n.思想體系，意識(shí)形態(tài)(a set of doctrines or beliefs that form the basis of a political, economic, or other system)

詞根記憶：ideo(思想)+logy--思想體系

派生詞：ideological(a．思想體系的)

3.idiosyncrasy n．癖好，特性（eccentricity）

詞根記憶：idio(個(gè)人的，獨(dú)特的)+syn(共同)+crasy(混合)--混合了個(gè)人特性的行為--癖好

例：idiosyncrasies of behavior行為特性

派生詞：idiosyncratic（a．特殊的，異質(zhì)的）

同根詞：idiom(n．習(xí)語(yǔ))：idiopathy (n．特發(fā)病)

4.idle a．閑置的(not turned to normal use)；無(wú)用的(vain)；懶散的(lazy)

例：In this country, growers of certain crops were paid to leave a portion of their land idle.//What you have said is an idle boast.

派生詞：idleness(n．閑散，懶惰)

5.ignite v.點(diǎn)燃(to kindle)；著火(to catch fire)

詞根記憶：ign(點(diǎn)燃)+ite--點(diǎn)燃，著火

例：Forest fires were ignited by a meteorite impact.

派生詞：ignition(n．點(diǎn)火，著火)

6.illegal a．違法的，非法的(unlawful，illicit)

詞根記憶：iI（不）+legal(合法的)--不合法的--違法的

例：illegal drugs違禁藥物

派生詞：illegally( ad.非法地，違法地)

7.illicit a．違法的，不正當(dāng)?shù)模╱nlawful）

詞根記憶：iI（不）+licit(合法的)--不合法的--違法的

例：illicit trade非法貿(mào)易

8.illiterate n.文盲(having little or no education; ignorant)

詞根記憶：il（不）+literate(識(shí)字的)--不識(shí)字的--文盲

例：People between 18 and 24 are more likely to be technologically il1ite,ate than somewhat older adults.

派生詞：illiteracy(n.文盲;無(wú)學(xué)識(shí))

9.illuminate v.照明(to light)；說(shuō)明(to make clear)

詞根記憶：il（加強(qiáng)）+lumin（明亮）+ate--照明

例：Could you please illuminate your theory worth a little more explanation?

同根詞：luminous(a.發(fā)光的：明亮的)