If you call this with argument "unused=true" it searches for the translation strings that exist in en_US but are never used.
IMPORTANT: that can take quite a lot of time (up to 10 minutes), you need to tune the max_execution_time on your php.ini accordingly.

Duplicate strings in lang files in /home/countryoaksconne/public_html/dolibarr_backup/dev/translation/../../htdocs/langs/en_US/ - 52 found

#StringFile and lines
26InvoiceSubtypebills.lang (679 - Invoice Subtype)
main.lang (1308 - Invoice subtype)
34AccountancyCodecompanies.lang (307 - Accounting account)
main.lang (898 - Accounting Code)
3IdModuleadmin.lang (141 - Module ID)
modulebuilder.lang (2 - Module id)
4NoticePeriodadmin.lang (295 - Notice period)
holiday.lang (127 - Notice period)
5LanguageFileadmin.lang (404 - Language file)
modulebuilder.lang (57 - File for language)
6PriceFormatInCurrentLanguageadmin.lang (449 - Price Format In Current Language)
companies.lang (33 - Price display format in the current language and currency)
7Upgradeadmin.lang (1211 - Upgrade)
install.lang (100 - Upgrade)
8Serveradmin.lang (1222 - Server)
install.lang (45 - Server)
9DatabaseServeradmin.lang (1224 - Database host)
install.lang (48 - Database server)
10DatabaseNameadmin.lang (1225 - Database name)
install.lang (49 - Database name)
11Buyadmin.lang (1900 - Buy)
products.lang (56 - Purchase)
12Selladmin.lang (1901 - Sell)
products.lang (55 - Sell)
13CashDeskadmin.lang (1937 - Point of Sale)
cashdesk.lang (3 - Point of sale)
14ByDefaultInListadmin.lang (2116 - Show by default on list view)
categories.lang (98 - By default in list)
1LineIdaccountancy.lang (146 - Id line)
exports.lang (45 - Id of line)
2CustomerInvoicePaymentaccountancy.lang (253 - Payment of invoice customer)
banks.lang (109 - Customer payment)
15AffectedToagenda.lang (11 - Assigned to)
projects.lang (124 - Allocated to)
16Locationagenda.lang (15 - Location)
stocks.lang (38 - Location)
17ReceptionClassifyClosedInDolibarragenda.lang (71 - Reception %s classified closed)
receptions.lang (50 - Reception %s classified Closed)
18InterventionSentByEMailagenda.lang (89 - Intervention %s sent by email)
interventions.lang (48 - Intervention %s sent by email)
19DeleteTypeassets.lang (21 - Delete)
members.lang (99 - Delete)
20ShowTypeCardassets.lang (24 - Show model '%s')
members.lang (169 - Show type '%s')
21IBANbanks.lang (33 - IBAN number)
bills.lang (505 - IBAN)
22BICbanks.lang (34 - BIC/SWIFT code)
bills.lang (510 - BIC/SWIFT)
23SubscriptionPaymentbanks.lang (111 - Subscription payment)
members.lang (183 - Contribution payment)
24InvoiceRefbills.lang (367 - Invoice ref.)
receiptprinter.lang (72 - Invoice ref)
25Salariesbills.lang (678 - Salaries)
salaries.lang (7 - Salaries)
27NoSupplierOrderboxes.lang (83 - No purchase order recorded)
orders.lang (87 - No purchase order)
28ShowCompanycashdesk.lang (32 - Show company)
companies.lang (323 - Third Party)
29Historycashdesk.lang (74 - History)
suppliers.lang (8 - History)
30DeleteFromCatcategories.lang (83 - Remove from tags/category)
compta.lang (294 - Remove from accounting group)
31Customercommercial.lang (4 - Customer)
companies.lang (261 - Customer)
32Prospectcommercial.lang (6 - Prospect)
companies.lang (258 - Prospect)
propal.lang (12 - Prospect)
33ShowTaskcommercial.lang (19 - Show task)
projects.lang (41 - Show task)
35ContractStatusClosedcontracts.lang (9 - Closed)
products.lang (90 - Closed)
36MinimumAmountdonations.lang (27 - Minimum amount is %s)
members.lang (215 - Minimum amount of membership payment (has priority on any default amounts))
37NewSubscriptioneventorganization.lang (121 - Registration)
members.lang (79 - New contribution)
38ExportsAreaexports.lang (3 - Exports)
other.lang (297 - Exports area)
39ExportableDatasexports.lang (7 - Exportable dataset)
other.lang (301 - Exportable data)
40AvailableFormatsexports.lang (29 - Available Formats)
other.lang (298 - Available formats)
41ChooseFileToImportexports.lang (68 - Upload file then click on the %s icon to select file as source import file...)
stocks.lang (254 - Upload file then click on the %s icon to select file as source import file...)
42CreateUserinstall.lang (55 - Create user account or grant user account permission on the Dolibarr database)
users.lang (31 - Create user)
43CreatedByother.lang (130 - Created by %s)
ticket.lang (169 - Created by)
44Stockproducts.lang (51 - Stock)
stocks.lang (18 - Stock)
45Stocksproducts.lang (53 - Stocks and location (warehouse) of products)
stocks.lang (19 - Stocks)
46Movementsproducts.lang (54 - Movements)
stocks.lang (29 - Movements)
47Suppliersproducts.lang (95 - Vendors)
suppliers.lang (2 - Vendors)
48Unitproducts.lang (185 - Unit)
stocks.lang (45 - Unit)
49ContractSignedpropal.lang (98 - Contract signed)
recruitment.lang (48 - Contract signed)
50WithdrawalReceiptsalaries.lang (32 - Credit transfer order)
withdrawals.lang (12 - Direct debit order)
51OrderWaitingsalaries.lang (33 - Pending order)
withdrawals.lang (94 - Waiting for treatment)
52NewUserticket.lang (305 - New user)
users.lang (30 - New user)