They were designed by Electric Boat and were built by other yards under subcontracts .
They were designed by Electric Boat and were built under subcontracts by other shipyards .

Are these two sentences paraphrases of each other?
yes

The Chief Justice was the Chief Justice of the High Commission territories ( Swaziland , Bechuanaland Protectorate , Basutoland ) , and from 1951 onwards were Chief Justices :
The Chief Justice was the Chief Justice of the High Commission ( Basutoland , Bechuanaland Protectorate , Swaziland ) , from 1951 the Chief Justices :

Are these two sentences paraphrases of each other?
yes

Stevens was a Republican when the party was founded , and was a delegate to the Republican National Conventions in 1860 and 1868 .
Stevens was a Republican when the party was formed , and became a delegate to the Republican National Conventions in 1860 and 1868 .

Are these two sentences paraphrases of each other?
no

The cancellous skeleton is organized in three layers : a compact basal lamellar layer , a dermal spongiosa , and a superficial lamellar layer .
The dermal skeleton is organized in three layers : a superficial lamella layer , a spongiosa spongiosa and a compact basal lamellar layer .

Are these two sentences paraphrases of each other?
no