常見(jiàn)例句By applying a mathematical transform to the coupling control equations about the phonon field and phason field, two standard wave equations and four speeds of wave are founded. 考慮一維準(zhǔn)晶體制備的桿的縱向波動(dòng)問(wèn)題,對(duì)聲子場(chǎng)和相位子場(chǎng)相耦合的控制方程進(jìn)行數(shù)學(xué)變換,得出2個(gè)標(biāo)準(zhǔn)的波動(dòng)方程和4種波速。Power Train The ZF electro-hydraulic shift transmission incorporated has four speeds forward and three reverse, and gear "kick-down" (KD) function with operational easy and efficiency. 變速系采用ZF電液換檔前四后三變速箱,具有自動(dòng)檔位切換開(kāi)關(guān)(KD鍵功能),操縱簡(jiǎn)便,工作效率高;The speed of sound in water is about four as great as in air. 聲音在水中的速度是空氣中的四倍左右It is clear to all of us that two plus two is four. 二加二等于四對(duì)我們大家都很清楚。He wove four plots together into a novel. 他把四條情節(jié)編成一部小說(shuō)。We have tea at four o'clock in the afternoon. 我們?cè)谙挛缢狞c(diǎn)鐘喝茶。 返回 four-speed