Commentary: Syntax is: NP1[agent] STRENGTHEN NP2[patient]
The trade agreement strengthened ties between the nations.
The good nutrition will help to strengthen his immune system.
These additives strengthen the steel.
WordNet 3.0 Sense Numbers: 1, 3
Commentary: Syntax is: NP1 STRENGTHEN (PP[instrument])
The hurricane strengthened over the ocean.
The town's opposition to the new mall is strengthening.
WordNet 3.0 Sense Numbers: 2