Costas Synolakis says Japan's concrete sea walls were not built to handle such high waves.

VOA: special.2011.03.21

It's an interesting question as to whether he really explains how a child goes from a concrete thinker to an abstract thinker, or how he goes from not having object permanence to understanding object permanence.

问题是,他是否真的解释了,儿童思维是如何从具体向抽象转变的,或是真的解释了,儿童的客体永存性概念是如何从无到有的

耶鲁公开课 - 心理学导论课程节选

So I am not just talking about agreement in principle but concrete results regarding spending and solidarity,".

VOA: standard.2009.03.20

Earlier this week African delegates boycotted some talks because they said developed nations were not making concrete promises on cutting greenhouse gas emissions.

VOA: standard.2009.11.06

"This is not a mere suspicion or speculation, some concrete indications of this possibly have been received."

VOA: standard.2009.09.25

Both matters are to be addressed, but concrete agreement on either is not expected.

VOA: standard.2009.04.01

U.S.officials indicated that they're prepared to wait a few more days for an Iranian response to the nuclear proposals, but that the Obama administration expects concrete action and does not have unlimited patience.

VOA: standard.2009.10.24

U.S.officials say they're willing to wait a few more days for an Iranian response to the nuclear proposals, but they say the Obama administration is looking for concrete action and does not have unlimited patience.

VOA: standard.2009.10.24