Banners and drums [in battle] are about the same
Indicates opponents are evenly matched
Neutral
两军对垒，旗鼓相当，胜负难以预料 | Liǎng jūn duìlěi, qígǔxiāngdāng, shèng fù nányǐ yùliào
The two armies were equally matched as they faced one another, and it was difficult to predict the victor
[Source]
小王和小张的学习成绩都是本班的第一名，这次英语演讲比赛两人都参加，真是旗鼓鼓相当啊 | Xiǎo Wáng hé Xiǎo Zhāng de xuéxí chéngjī dōu shì běn bān de dì yī míng, zhè cì yīngyǔ yǎnjiǎng bǐsài liǎng rén dōu cānjiā, zhēnshi qígǔxiāngdāng a
Little Wang and Little Zhang's grades are the highest in their class, and they both are participating in the the English competition. They're really evenly matched!
[Source]
None
None
None
《后汉书》(Hòu Hàn Shū, "History of the Eastern Han") by 范晔 (Fàn Yè)
At the beginning of the eastern Hàn Dynasty (东汉, 25 - 220), the new Hàn emperor 刘秀 (Liú Xiù, also known as 光武帝/Guāng Wǔ Dì) had not yet fully unified the land. In modern-day 四川 (Sì Chuān) province, the warlord 公孙述 had declared himself emperor, and in modern-day 甘肃 (Gān Sù) province, 隗嚣 (Wěi Xiāo) wielded considerable power as well.
Now, 公孙述 and 隗嚣 did not get along well, and they battled frequently. 刘秀 knew that he didn't have enough troops to fight the both of them separately, and he realized he could use their animosity towards one another to his advantage. He reached an agreement with 隗嚣 in which 隗嚣 pledged allegiance to him in exchange for a position as a general in his army.
The war against 公孙述 continued, and soon, 公孙述's forces started pressing towards 刘秀's capital city of 长安 (Chǎng Ān). 刘秀, seeing part of his forces unable to withstand the onslaught, quickly wrote his new general a letter asking for assistance. In the letter, he indicated that with the help of his forces, he could go head-to-head (旗鼓相当) with 公孙述. 隗嚣 complied, and 公孙述 suffered a defeat.